Tuesday, 23 February 2016

Coolant leak from under the engine block - water/oil pump weep hole - Yamaha YZF-R1 2004 2005 2006

Jeezes, a water leak again! after I fixed a metal pipe on the front of the bike, all of a sudden, I had a tiny coolant leak, this time from under the engine block. Since it was tiny, I didn't think much of it. But gradually the amount got bigger and bigger. I am using this R1 as my daily ride, so it is super annoying, so what do I do, I throw some liquid radiator leak stop in there, didn't work much, so I threw in another bottle....I know, after all the mechanical work I did on this bike, which I am able to do, this is not a great fix... One day I was going to tackle the problem, So i suspected that it was the thermostat housing again as I had a leak there once, which I fixed by replacing it, so I removed the tank, to check that, result: bonedry...

Where is the coolant leak coming from?? Looking under the bike, it only leaks when you start the engine. Drop by drop, not much.

It was dark so I thought, fuck, it must have been those road bumps where sometime the bottom of the bike touches on, I really believed that I was screwed and that my engine block had a crack.

But wait? Coolant water from the oil carter?? That's where I figured out that the bike has an oil/water pump that sits in the oil carter (bottom pan of engine) and that there is actually a purposely made hole there for when this happens: oil/water pump seal failure!!!

Guess what: I have to replace the oil/water pump for this R1....And it ain't looking pretty..... From lookig at the manuals you have to remove the plastic covers, take out the clutch basket, the exhaust headers and complete exhaust, then remove the bottom carter of engine.... Not sure when I will do this. So far, the radiator leak is holding up and no more leaks.

It actually closed the weep hole up.. It's probably not so great but all is fine so far.

I think I will be selling this bike and tell the prospective buyer what needs to be done.